Frontiers of Science: Quantum Computer – Waves

Ambience: ocean waves

Waves – they’re one way of understanding how the next generation of computers will work their magic. I’m Jim Metzner and this is the Pulse of the Planet. Let’s say you’ve got a thorny computer problem that involves going through many potential solutions, like decrypting a message for example. Well in the future, the tool of choice for solving this sort of problem quickly might well be a quantum computer, which uses the rules of quantum mechanics to explore many possibilities at once.

Piilonen: It comes down to interference of waves.

Leo Piilonen heads the physics department at Virginia Tech.

Piilonen: If you throw a rock into a pond, you’ll have a wave. If you throw two rocks into the pond at two different places, you’ll have the waves from the two rocks ripple out. And eventually, the ripples of those waves will overlap. So in quantum computing, we’re taking advantage of that kind of wave overlap to explore all the possibilities of how you could go from Point A to Point B.

The language of quantum computing is going to be mathematical formulas for solving problems, like how to get from point A to point B, how to decrypt a message, or even how to predict the behavior of waves.

Piilonen: Imagine that you have a wave that is approaching a barrier. And in the barrier are two very small holes that will let the waves go through. So then, the waves that emerge from these two small holes on the other side of the wall start to spread out, and eventually, they will interfere with each other. And if you have people stationed far away from the wall in a line looking at the interference of these two waves, each person will see a different result. It’s that simultaneous observation of all the different ways that these two starting waves at the wall can interfere with each other that you can explore all the different possibilities all simultaneously. And the waves on the surface of water are analogous to the quantum waves that we can prepare in our quantum computer.

Pulse of the Planet is made possible in part by the National Science Foundation. I’m Jim Metzner.